LOAN SERVICING RIGHTS - Schedule of Activity of Servicing Rights (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	$ 212,500
Ending balance	237,620
Residential mortgage servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	206,944	$ 130,630
Additions	21,701	21,867
Amortization	(6,062)	(7,484)
Recoveries	9,653	9,733
Ending balance	232,236	154,746
Residential mortgage servicing valuation allowance
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	25,782	39,407
Recoveries	(9,653)	(9,733)
Ending balance	16,129	29,674
SBA servicing rights
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	5,556	5,839
Additions	538	230
Amortization	(710)	(529)
Recoveries	0	905
Ending balance	5,384	6,445
SBA servicing valuation allowance
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	0	905
Recoveries	0	(905)
Ending balance	0	0
Indirect automobile
Servicing Asset at Fair Value, Amount [Roll Forward]
Beginning balance	0	73
Amortization	0	(44)
Ending balance	$ 0	$ 29

The periodic amortization (in proportion to and over the period of estimated net servicing income or loss) of capitalized servicing rights, which contractually entitle the servicer to receive fees and ancillary revenues for performing billing, collection, disbursement and recordkeeping services in connection with a mortgage portfolio. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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- Definition

The adjustment to the carrying value of the rights retained or purchased to service mortgages. These adjustments are made when the estimate of the fair value is changed. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
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- Definition

The value of new servicing assets, subsequently measured at fair value, acquired or created during the current period through purchases or from transfers of financial assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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- Definition

Fair value of an asset representing net future revenue from contractually specified servicing fees, late charges, and other ancillary revenues, in excess of future costs related to servicing arrangements.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
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